行乐及时: make merry while one can; enjoy at the right time; enjoy pleasure in good time; live while we may
恣意行乐: give way to unrestrained fun [joy]; allow one to act freely in pleasure-seeking
及时行乐: enjoy pleasure in good time; enjoy the pleasures of life here and now; enjoy the sweets of life while one is young; make merry while one can; carpe diem